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| Sunday, 30 October 2005 |
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Features |  |
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Environment
Antarctic glaciers slipping faster into the ocean The edges of the Antarctic ice sheets are slipping into the ocean at an unprecedented rate, raising fears of a global surge in sea levels, glaciologists warned on Monday.
In one area, around the Amundsen Sea in West Antarctica, glaciers are dumping more than 110 cubic kilometres of ice into the ocean each year, Eric Rignot of NASA's Jet Propulsion Laboratory in California, US, told a meeting at the Royal Society in London, UK. This loss, which is increasing each year, is many times faster than the ice can be replaced by snowfall inland, he says. The impending ice disaster centres on Pine Island Bay on the shores of the Amundsen Sea, where the Pine Island and Thwaites glaciers enter the sea. These glaciers, like many in West Antarctica, are perched on underwater mountains. The meeting heard that warmer ocean waters are circulating beneath the ice and melting their bases at a rate of 50 metres a year. As this happens, the glaciers float clear of the submarine mountains and slide into the ocean. According to Andy Shepherd at the University of Cambridge, UK, they are discharging ice three times faster than a decade ago. These glaciers are being dubbed the "plug hole" of the West Antarctic Ice Sheet. If the Pine Island and Thwaites glaciers disappeared, they alone could raise sea levels worldwide by more than a metre, says Rignot. Antarctic glaciers are much bigger than those in warmer climates. They are up to a kilometre thick, tens of kilometres wide and hundreds of kilometres long. Connected to inland ice tributaries, they drain the continent's ice caps, which are the largest stores of frozen water on the planet. In many places, the glaciologists reported that the recent acceleration in glacier flows has been triggered by the break-up of a series of floating ice shelves at the continent's edge. These shelves acted like a cork in a bottle, holding back the glaciers. After the Larsen B ice shelf - a 3000 square kilometre floating slab of ice - broke up over three days in 2002, glaciers behind it afterwards accelerated eight-fold. "The ice mass balance of Antarctica is controlled by these ice shelves," says Rignot, who believes Antarctica is now responsible for the majority of global sea level rise. Researchers also warned that the larger East Antarctic Ice Sheet is not as stable as thought. A recent study suggested that it might be accumulating snow in its high interior - possibly supporting the IPCC's predictions - but it warned that little was known about events on the coast (Science, vol 308, p 1898). Rignot revealed that several major coastal glaciers in the east are now known to be accelerating, like their counterparts to the west. NewScientist IUCN awarded President's Environmental Award The World Conservation Union (IUCN) has been awarded the President's Environmental Award for excellent environmental services under the INGO sector for the year 2004. IUCN Sri Lanka's mission is "To influence, encourage and assist societies throughout the world to conserve the integrity and diversity of nature and to ensure that any use of natural resources is equitable and ecologically sustainable". It's vision, "A just society that values and conserves Sri Lanka's nature and natural resources in a sustainable and equitable manner". The IUCN Sri Lanka Country Office was established back in 1988. Since then, IUCN has been working closely with the government of Sri Lanka, NGO members and partners to facilitate conservation in Sri Lanka. IUCN's presence in Sri Lanka now includes the Sri Lanka country office, Regional Biodiversity Program, Regional Marine Program, Regional Environmental Economic Program and the Regional Species Program. IUCN plays a catalytic role and offers effective platforms to promote dialogue and discussion amongst various partners engaged in conservation work, provides opportunities for the practical application of methodologies developed through the Union's scientific networks and supports conservation initiatives of members and partners of IUCN in Sri Lanka in biodiversity conservation, conservation and management of critical habitats, environmental policy support, institutional support and environmental education and awareness. Marine species in danger Seafood prices on restaurant menus as far back as the 1860s have helped scientists track the impact of over-harvesting on marine species. They also reveal changing tastes among the restaurant-going public. The study of US menus held in library and university collections could help inform the conservation of modern stocks, say the authors. The results will be presented at a conference on the history of marine animal populations in Denmark. The power of using the menus, is that you can take that relationship from the 1950s to-date and extend it back 100 years. Glenn Jones of the Texas A and M University looked at National Fisheries Service records going back to the 1950s of seafood landings and their dollar value. They then compared these with the retail prices from the menus. "There's a very strong correlation between those data sets," said project leader Dr Glenn Jones of Texas A and M University at Galveston, Texas. "The power of using the menus, is that you can take that relationship from the 1950s to-date and extend it back 100 years in time." Lobster was one of the species looked at by the researchers. Prior to the 1880s, it was unusual to see lobster on menus. But tastes changed around the beginning of the 20th Century. By the 1950s, prices ballooned, with restaurants pricing lobsters at one-quarter pound (113g) weight increments. Dr. Jones and his colleagues interpret this as a reflection of declining stocks. The study also shows a dramatic rise in the price of abalone coinciding with the collapse of stocks along the Californian coast. "Abalone has seen a 10-fold rise in its price since the 1920s," Dr. Jones told the BBC News website. The researchers still need to carry out sorting of the five-star restaurants from two-star restaurants, which will give them a more detailed understanding of changing tastes and fluctuations in the price of different species. Many of the collections were donations by private enthusiasts. "When you think about it, a menu was a piece of ephemera, it wasn't meant to be saved, but thankfully, some people collected them," said Dr. Jones. "We believe this is the first time anyone has tried to work with this treasure trove of historical information." The preliminary results will be presented at the Oceans Past conference in Kolding, Denmark, which runs from the 24-27 October. It has been organised by the Census of Marine Life, a 10-year project to give a baseline assessment of the state of our oceans today. "To gain a sense of perspective on that, you need a historical counter-image," commented Poul Holm, who leads the History of Marine Animal Populations (HMAP) arm of the Census of Marine Life. - BBC News Animals 'hit by global warming' A report commissioned by the UK Government warns that climate change could lead to the extinction of many animals including migratory birds. Among the threats identified are melting ice, the spread of deserts and the impact of warm seas on the sex of turtles. The report also confirmed that warming has already changed the migration rates of some birds and other animals. The UK's Department of Environment, Food and Rural Affairs (DEFRA) commissioned the research, which was led by the British Trust for Ornithology. The report is being launched at a meeting of EU nature conservation chiefs in Aviemore, Scotland. This meeting was called to discuss ways in which wildlife might be helped to adapt to global warming. Scientists have already observed a worryingly wide range of changes in the migration patterns of birds, fish and turtle, which appears to be in response to warming which has already taken place. While many species have managed to adapt to new conditions by moving their ranges further towards the poles, the report warns that this is not possible for other animals, such as polar bears and seals whose habitat is rapidly disappearing with the melting of Arctic sea ice. The report also highlighted that even subtle changes in sea temperature can have a dramatic effect on wildlife, such as the depletion of plankton organisms which form the base of the oceans' food web. Humphrey Crick from the British Trust for Ornithology, one of the report's authors, explains, "there is some scope for helping species adapt to climate change, but we need to find global solutions to help animals that swim, fly and walk thousands of miles each year." The main fear brought up by the report, is that the changes currently underway are just too rapid for species to evolve new survival strategies. - BBC Wildlife Magazine. |
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| Produced by Lake House |
The findings confound predictions made just four years ago, by the UN's
Intergovernmental Panel on Climate Change (IPCC), that Antarctica would not
contribute significantly to sea level rise in the 21st century. 
